Digital Hearing Aid May Be The Answer For Hearing-Impaired

"No hearing aid so far has been very effective in noisy situations. In fact, I left industry and came to academia in order to have more time to work on this goal," says the associate professor of electrical engineering at Washington State University in Spokane. She also directs WSU's Microelectronics Laboratory in Spokane.

Originally her research specialty was quantum electronics with secondary interest in optical communications and solid state devices. Working on laser radar and optical surveillance problems, she quickly realized that signal processing was critical to system performance. Although she later moved on to semiconductor device manufacturing as well as signal processing, she says, "I kept up the strong interest in signal processing because of my hearing loss."

Additionally, Mortz is currently working on a "speech enhancement for elderly listeners" project with Nancy Vaughan, assistant professor of speech and hearing sciences at WSU Spokane. There is evidence the difficulties older listeners have in understanding speech may be related to their ability to process incoming speech efficiently. With two graduate students, Mortz and Vaughan are developing digital signal processing methods to selectively strengthen consonants and to slow down the speaking rate without causing pitch distortions.

"Ultimately a wearable device similar to a hearing aid could provide real-time slowing of the rate of speech, thus improving a listener's comprehension," says Mortz.

She is now conducting feasibility investigations on speech enhancement techniques to improve speech understanding in noise. Among other things, the procedures used can pick out certain soft sounds such as consonants and make them louder.

Cooperating with other researchers at WSU, Eastern Washington University, and the University of Idaho, Mortz has helped start the Center for Acoustical Engineering for Living Systems at the Spokane Intercollegiate Research Technology Institute. The center provides a forum linking researchers in the Inland Northwest and focuses on the development of acoustic-related products that could be sold commercially within five years. Those products may range from wearable speech-enhancement systems to tools for the acoustic detection of cancer. "A lot of what I'm doing is acting as bridge between companies and researchers," she says.

With EWU faculty, Mortz is conducting preliminary investigations of signal and pattern processing techniques using photoacoustics for application to a system for biological warfare agent detection and classification. Initial development will be with similar, but non-lethal organisms. Eventually the system would be able to detect several biological and chemical agents like harmful air pollutants or spores of mold and bacteria for commercial applications.

Other industry-related collaborative research involves developing signal processing algorithms for a project to digitally remove the effects of scratches and defects on vinyl records for re-recording onto CD-ROMs for library use.

As coordinator for electrical engineering and computer science at WSU Spokane, Mortz is looking for guidance from Spokane companies on the type of engineering classes that will benefit local engineers. She's also seeking companies that need specialized research or those companies that could benefit from the microelectronics laboratory.

After earning doctorate at UCLA, Mortz taught at the University of Denver, and spent 13 years in private industry.